Malicious PDF — malware analysis report

Static analysis result for SHA-256 26b651151a8ecc2e…

MALICIOUS

PDF

88.3 KB Created: 2021-09-10 10:53:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 63a0d96d394074d6a8003d675cbf63de SHA-1: a73f3f0b32ffaf83b2695d0122207f6da7543a7d SHA-256: 26b651151a8ecc2e81e75d3e743299a250f8f02a92ccf87d8df7d1fd64abcf16
134 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The sample was identified as malicious by a ML classifier and ClamAV, with critical heuristics indicating embedded JavaScript and external URIs. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests a large number of links pointing to potentially disposable domains, indicating a link farm or phishing infrastructure. The embedded JavaScript is likely responsible for redirecting users to these external URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.huntsvillepr.com/files/files/sofijidavizaribigorijiwo.pdf In PDF document text
    • https://guclupin.com/calisma2/files/uploads/63433216262.pdfIn PDF document text
    • http://ozgu-yapi.com/firma/files/42446088248.pdfIn PDF document text
    • http://ned.ru/uploads/files/56389107779.pdfIn PDF document text
    • https://gulfcans.com/home/madarmun/public_html/gulfcans/images/bulk_images/files/75501737037.pdfIn PDF document text
    • https://aymexco.eu/ckfinder/userfiles/files/78983682444.pdfIn PDF document text
    • https://eownauto.com/uploadpic/files/mumonukanetesefofasaru.pdfIn PDF document text
    • http://carneiro-sa.pnh.pt/js/ckfinder/userfiles/files/tudaferolakojabowuzesu.pdfIn PDF document text
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1613496c931253---76425769163.pdfIn PDF document text
    • http://ballmillfactory.com/d/files/58595147061.pdfIn PDF document text
    • https://nhahangphongcanh.com/uploads/files/wuxelanogitejaxikusag.pdfIn PDF document text
    • https://doucetplasticsurgery.com/ckfinder/userfiles/files/10363804943.pdfIn PDF document text
    • http://eminenceinc.com/userfiles/file/xatejalemax.pdfIn PDF document text
    • http://lagunaapartman.hu/images/user/file/51591974561.pdfIn PDF document text
    • http://xn--80ahcjevtqq.xn--p1ai/ckfinder/userfiles/files/pabomubokinuxadajerisovu.pdfIn PDF document text
    • http://lyzph.com/userfiles/file/Fl202109090512565073.pdfIn PDF document text
    • https://icnj.net/ckeditor/ckfinder/userfiles/files/39698503130.pdfIn PDF document text
    • http://www.moyekolodin.com/files/ravenuniwe.pdfIn PDF document text
    • http://klm-co.ru/foto/ck/files/lulukiraketanixelufu.pdfIn PDF document text
    • http://kirakuramen.com/uploads/files/24365544453.pdfIn PDF document text
    • http://conflictfreeelectronics.com/ourprojects/chowki/UserFiles/renuka/file/lufex.pdfIn PDF document text
    • https://ijmscr.com/ckfinder/userfiles/files/46916329288.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=upload+multiple+image+to+server+in+android+using+multipart+examplePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f092.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF092 11008 bytes
SHA-256: 80b3dbf40dd41d80e86170b196df106e1dda7d4b3d5bfc8e4b4433390c16706b
font_01_sfnt_off000109f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109F3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012205.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12205 18672 bytes
SHA-256: c9877b8b5fddb253e76b78af8cc419f38c5b1c70571aebe8487d5584160e3d92